It is frequently necessary in industrial and transportation applications to have access to the interior of storage compartments. A typical example of such is an ullage tube, that is, a tubular member extending from the top of a bulk storage area providing access to the storage area. Such ullage tubes frequently are provided with hinged closures. In many instances it is desirable that the storage compartments be observable through such ullage tubes. For this reason, many applications exist wherein sight glasses or viewport assemblies are required in conjunction with ullage tubes.
While others have provided viewport assemblies for ullage tubes, the devices which have been heretofore in common commercial practice have not been entirely successful. In today's economically sensitive environment more effective sealing of storage compartments is required. In addition, modern transportation facilities have a greater emphasis on cleanliness and sanitation which have not been easily accomplished with previously employed viewport assemblies.
The present disclosure is an improved viewport assembly for use in conjunction with an ullage tube or any such similar tubular access. An object of the present disclosure is to provide a viewport assembly that more effectively seals an ullage tube to prevent the escape of liquids and/or gases from within the storage area to which the ullage tube connects and, in like manner, to prevent contamination by fluids, gases, dust, or other foreign material from passing through the ullage tube into the storage compartment.
In order to improve cleanliness, an object of this disclosure is to provide a viewport assembly for an ullage tube including a transparent window removably fittable within the ullage tube and in which the entire assembly presents a substantially flush surface coincident with the end of the ullage tube to thereby minimize water and other contaminants that might collect on top of the closed ullage tube.